Recently, personal computers or the like have been used to create multimedia content by combining content such as graphics, texts, photographs, sounds, and the like. In creating multimedia content, an operation of arranging and editing content on a canvas appearing in a display region is essential.
When the size of the canvas is larger than the size of the display region on the display, however, the content arranged on the canvas may not be displayed as a whole within the display region. In this case, the user displays the content to be edited in the display region by reducing the scale in the display region or by scrolling the display region. Japanese Patent Laying-Open No. 1-306916 discloses a technique of displaying desired content within a display region by automatically scrolling the display region.
Japanese Patent Laying-Open No. 1-306916 discloses a graphic input device that detects coordinates of an input graphic and draws a graphic on a display screen. The graphic input device includes determination means for determining whether an input position of coordinates is within a predetermined graphic input valid region, and scroll controlling means for scrolling the region to bring the input position into the region when the determination means determines that the input position is outside the region.
In this graphic input device, if, at the input of graphics or the like, the coordinates outside the predetermined graphic input valid region are designated, the screen is automatically scrolled. This eliminates the need for a cumbersome operation of suspending an operation of inputting graphics or the like during this operation to give an instruction of scrolling. Thus, the operability can be improved.
Meanwhile, small equipment such as a mobile phone has improved in processing ability so that multimedia content can be created by arranging content.
In the small equipment such as a mobile phone, since the size of the display region is often smaller than the canvas size, it frequently happens that the canvas does not fit into the display region. Therefore, the content as an operation target that the user wants to operate is often positioned outside the display region.
In order to avoid the situation described above, the entire canvas may be reduced in size to fit into the display region to be displayed. However, if it is displayed in a reduced size on the display screen of the small equipment, which is naturally small, the operation target arranged on the canvas becomes smaller and finer, which adversely deteriorates the operability for the user. In addition, the processing ability of the small equipment such as a mobile phone may not be sufficient, and thus the reducing operation may be difficult when the number of operation targets increases.
Moreover, in some applications, automatically scrolling the display region, as with the method disclosed in Japanese Patent Laying-Open No. 1-306916, is not necessarily appropriate.
For example, suppose that an animation product is created in which a ball appears from the left of the display region, moves across the display region, and then disappears at the right of the display region. In order to create it while grasping the range in which the final product can be viewed, the display region during the operation is desirably matched with the display region during a replay of the animation. In this case, it is uncertain in which direction the display region should be scrolled, since the operation target is located outside the display region.